In physical design of a semiconductor integrated circuit such as a LSI (Large Scale Integrated circuit), there is a known technology regarding a design support apparatus (CAD (Computer Aided Design) apparatus) for performing automatic wiring upon movement of a circuit block on a screen displayed on a monitor.
Regarding the automatic wiring, the following technique is known. That is, regarding a net (a connection (logical connection) between terminals in a circuit) for which wiring is to be performed, or between the terminals, after the terminals included in the net or a cell (a circuit component serving as a unit for placement in physical design) having the terminals is placed, an instruction for performing automatic wiring in the net or between the terminals is given, and as a result, wiring is performed so that the wiring is completed.
Also, a technique for determining in real time, whether wiring has to be repaired while visually checking the wiring on a screen is known.
In these techniques, an explicit instruction for performing automatic wiring is given after terminals included in a net or a cell having terminals has been placed. Therefore, there have been problems in that an instruction for performing automatic wiring cannot be given unless placement of the cell is completed, and in addition that whenever the wiring result is not suitable because of the placement position of the cell, an instruction for placing the cell again and performing wiring again needs to be given which makes the procedure complicated.
In consideration of such a point, an object of the invention is to provide a design support apparatus and a control method for the purpose of efficient wiring.    [Patent Document 1] Japanese Laid-open Patent Publication No. 8-96012    [Patent Document 2] Japanese Laid-open Patent Publication No. 2000-67101